Drazepinone, a trisubstituted tetrahydronaphthofuroazepinone with herbicidal activity produced by Drechslera siccans

When grown in a minimal-defined medium, a strain of Drechslera siccans, a pathogenic fungus isolated from seeds of Lolium perenne, produced phytotoxic metabolites. This strain is one of the best toxin producers among several grass pathogenic fungal strains collected and tested to find phytotoxins to be used as natural herbicides of monocot weeds. From the culture filtrates of D. siccans, we isolated a new phytotoxic trisubstituted naphthofuroazepinone, named drazepinone, and characterised it as a 3,5,12a-trimethyl-2,5,5a,12a-tetrahydro- 1H-naphtho[2′,3′:4,5]furo[2,3-b]azepin-2-one. Assayed at 2 μg μl-1 solution the novel metabolite proved to have broad-spectrum herbicidal properties, without antibacterial and antifungal activities, and low zootoxic activity. Its original chemical structure and the interesting biological properties make drazepinone a potential natural herbicide. © 2005 Elsevier Ltd. All rights reserved

Dirac dispersion and non-trivial Berry's phase in three-dimensional semimetal RhSb3

We report observations of magnetoresistance, quantum oscillations and angle-resolved photoemission in RhSb$_3$, a unfilled skutterudite semimetal with low carrier density. The calculated electronic band structure of RhSb$_3$ entails a $Z_2$ quantum number $\nu_0=0,\nu_1=\nu_2=\nu_3=1$ in analogy to strong topological insulators, and inverted linear valence/conduction bands that touch at discrete points close to the Fermi level, in agreement with angle-resolved photoemission results. Transport experiments reveal an unsaturated linear magnetoresistance that approaches a factor of 200 at 60 T magnetic fields, and quantum oscillations observable up to 150~K that are consistent with a large Fermi velocity ($\sim 1.3\times 10^6$ ms$^{-1}$), high carrier mobility ($\sim 14$ $m^2$/Vs), and small three dimensional hole pockets with nontrivial Berry phase. A very small, sample-dependent effective mass that falls as low as $0.015(7)$ bare masses scales with Fermi velocity, suggesting RhSb$_3$ is a new class of zero-gap three-dimensional Dirac semimetal.Comment: 9 pages, 4 figure

STOCHASTIC AND FULL-WAVEFIELD FINITE-FAULT GROUND-MOTION SIMULATIONS OF THE M7.1, MESSINA 1908 EARTHQUAKE (Southern Italy)

In the framework of an ongoing Italian national research project we are studying the Messina 1908 earthquake, the first to be recorded adequately by seismological and geodetic instrumentation that allowed subsequent quantitative investigations of its source properties. We use a high-frequency stochastic finite-fault modeling (Motazedian and Atkinson, 2005) to simulate the ground-shaking for a number of different source models (Basili et al. 2008), either constrained from past source studies of this event or simulated. Although inherently kinematic, our approach accounts for the physics of the source using a procedure to generate physically consistent earthquake-rupture models (Guatteri et al., 2004). Considering the width of the seismogenic zone and appropriate source-scaling relation, we generate heterogeneous slip models that obey to the source complexity of past earthquakes (Mai and Beroza, 2002). By also constraining the point of rupture initiation based on empirical findings and energy-balance arguments (Mai et al., 2005), we generate a suite of earthquake source models to compute far-field ground-shaking. The Housner parameter from the stochastic high-frequency simulations is than compared with the felt intensity (MCS scale). The developed procedure is a necessary tool to take into account the influence of directivity effects in simulating ground shaking scenarios using realistic slip distribution on the fault. Furthermore, we carry out full-wavefield ground-motion calculations (at frequencies f < 3 Hz) to compare those low-frequency simulations with (a) the stochastic simulations and (b) appropriate ground-motion prediction equations. The combined approach helps to examine the validation range of the two methods (distinguishing the influence of the near-field and far-field motions on the shaking level), and may serve as a basis to develop a hybrid technique which combines the two methods for generating fully broadband synthetic seismograms

LASER SCANNER AND CAMERA-EQUIPPED UAV ARCHITECTURAL SURVEYS

ABSTRACT: The paper reports the workflow of 3D modelling and photorealistic texture mapping based on close range imagery acquired through a terrestrial laser scan and a camera mounted on a mini Unmanned Aerial Vehicle (UAV). The 3D models of the same architectural object -a watchtower named &quot;Torre Pelosa&quot; (Bari, Italy) -were compared in order to evaluate strengths and weaknesses of the used instruments and methods. The evaluated parameters where geo-referencing capability, manageability, manoeuvrability, operational constraint, survey completeness and costs. Despite a lower accuracy of the results, the use of a UAV mounted camera is essential to obtain a whole representation of the tower

Effect of Pt substitution on the electronic structure of AuTe2

We report a photoemission and x-ray absorption study on Au1-xPtxTe2 (x = 0 and 0.35) triangular lattice in which superconductivity is induced by Pt substitution for Au. Au 4f and Te 3d core-level spectra of AuTe2 suggests a valence state of Au2+(Te2)2-, which is consistent with its distorted crystal structure with Te-Te dimers and compressed AuTe6 otahedra. On the other hand, valence-band photoemission spectra and pre-edge peaks of Te 3d absorption edge indicate that Au 5d bands are almost fully occupied and that Te 5p holes govern the transport properties and the lattice distortion. The two apparently conflicting pictures can be reconciled by strong Au 5d/Au 6s-Te 5p hybridization. Absence of a core-level energy shift with Pt substitution is inconsistent with the simple rigid band picture for hole doping. The Au 4f core-level spectrum gets slightly narrow with Pt substitution, indicating that the small Au 5d charge modulation in distorted AuTe2 is partially suppressed.Comment: 13 pages, 4 figures, accepted by Physical Review

Deliverable 2 # A3.13.8

We examine possibilities to delineate the boundaries between near-field and far-field radiation of seismic waves. Near-field (NF), intermediate-field (IF) and far-field (FF) terms represent different properties of the seismic wave-field: the near-source motions are sensitive to the spatio-temporal details of the rupture process, while far-field terms tend to carry the overall signature of the rupture. Due to the longer propagation path of far-field waves through complex Earth structure, their waveform properties also depend more strongly on media properties (scattering; intrinsic attenuation), than it is the case for the NF-wavefield

The momentum and photon energy dependence of the circular dichroic photoemission in the bulk Rashba semiconductors BiTeX (X = I, Br, Cl)

Bulk Rashba systems BiTeX (X = I, Br, Cl) are emerging as important candidates for developing spintronics devices, because of the coexistence of spin-split bulk and surface states, along with the ambipolar character of the surface charge carriers. The need of studying the spin texture of strongly spin-orbit coupled materials has recently promoted circular dichroic Angular Resolved Photoelectron Spectroscopy (cd-ARPES) as an indirect tool to measure the spin and the angular degrees of freedom. Here we report a detailed photon energy dependent study of the cd-ARPES spectra in BiTeX (X = I, Br and Cl). Our work reveals a large variation of the magnitude and sign of the dichroism. Interestingly, we find that the dichroic signal modulates differently for the three compounds and for the different spin-split states. These findings show a momentum and photon energy dependence for the cd-ARPES signals in the bulk Rashba semiconductor BiTeX (X = I, Br, Cl). Finally, the outcome of our experiment indicates the important relation between the modulation of the dichroism and the phase differences between the wave-functions involved in the photoemission process. This phase difference can be due to initial or final state effects. In the former case the phase difference results in possible interference effects among the photo-electrons emitted from different atomic layers and characterized by entangled spin-orbital polarized bands. In the latter case the phase difference results from the relative phases of the expansion of the final state in different outgoing partial waves.Comment: 6 pages, 4 figure

3D MODELLING AND MEDIEVAL LIGHTING RECONSTRUCTION FOR RUPESTRIAN CHURCHES

The aim of this research is to define a method, able to analyse the systems of illumination in the medieval period, through a 3D virtual model reconstruction. It specifically needs to deepen the interactions between natural and artificial illumination in confined spaces. The study describes and examines the best survey technique to obtain a 3D model reconstruction, according to the achievement of such lighting scenarios, and the most suitable tools for lighting analysis. Thus, it is possible to carry out accurate interpretations of the past starting from historical sources and scientific data about lighting. This method was validated on a case study of a rupestrian church in Matera. The rupestrian contexts are less investigated in relation to mediaeval artificial lighting even if there are recognitions and comparative studies of widespread contexts, not only in Puglia and Basilicata, but also in Mediterranean area (e.g. in Cappadocia and Cyprus) which allow identifying evidences related to artificial lighting systems. The architectural signs (hole, niches, etc.) for ancient luminaries can be studied in 3D and lighting prospective. Lastly, the virtual model of the rupestrian church was imported into an opensource visualisation software (3D Heritage Online Presenter) to be appreciable on line and to promote historical heritage knowledge

Deliverable 1 # A3.13.1-2-3-4-5

We investigate wave motion through numerical simulations that take into account primarily the ground acceleration in response to a given earthquake rupture that radiates seismic waves. The shaking that potential sources might cause is plotted on maps that provide a general overview of the hazard over a large area, and that can be used as the starting point for further detailed investigations. Here, we establish a procedure to compute ground motion that spans the entire frequency range of engineering interest (i.e., broad-band), and we derive the maximum shaking that is caused by expected earthquakes throughout Italy (i.e. the maximum observable shaking; MOS). Our approaches merge updated knowledge of the Italian regional tectonic setting and of source-zone definitions (Valensise and Pantosti, 2001; Basili et al., 2008) and scenario-like calculations of the expected MOS in any given area

Doping dependent charge order correlations in electron-doped cuprates

Understanding the interplay between charge order (CO) and other phenomena (e.g. pseudogap, antiferromagnetism, and superconductivity) is one of the central questions in the cuprate high-temperature superconductors. The discovery that similar forms of CO exist in both hole- and electron-doped cuprates opened a path to determine what subset of the CO phenomenology is universal to all the cuprates. Here, we use resonant x-ray scattering to measure the charge order correlations in electron-doped cuprates (La2-xCexCuO4 and Nd2-xCexCuO4) and their relationship to antiferromagnetism, pseudogap, and superconductivity. Detailed measurements of Nd2-xCexCuO4 show that CO is present in the x = 0.059 to 0.166 range, and that its doping dependent wavevector is consistent with the separation between straight segments of the Fermi surface. The CO onset temperature is highest between x = 0.106 and 0.166, but decreases at lower doping levels, indicating that it is not tied to the appearance of antiferromagnetic correlations or the pseudogap. Near optimal doping, where the CO wavevector is also consistent with a previously observed phonon anomaly, measurements of the CO below and above the superconducting transition temperature, or in a magnetic field, show that the CO is insensitive to superconductivity. Overall these findings indicate that, while verified in the electron-doped cuprates, material-dependent details determine whether the CO correlations acquire sufficient strength to compete for the ground state of the cuprates.Comment: Supplementary information available upon reques